PT-2026-115510 · Mattermost · Mattermost

·

CVE-2026-18560

·

Published

2026-10-16

·

Updated

2026-10-16

CVSS v3.1

4.3

Medium

VectorAV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to validate user’s permissions before other validations which allows non-content reviewers to infer a post’s flagged status via direct API call.. Mattermost Advisory ID: MMSA-2026-00754

Fix

Side Channel Attack

Found an issue in the description? Have something to add? Feel free to write us 👾

Weakness Enumeration

Related Identifiers

CVE-2026-18560

Affected Products

Mattermost